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Ω and φ in Au + Au collisions at (s_(NN))^(1/2)= 200 and 11.5 GeV from a multiphase transport model

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Chinese Physics C 2017年第8期41卷 71-77页

作者： Y. j. Ye j.h. chen Y.G. Ma S.Zhang C. Zhong Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049 China ShanghaiTech. University Shanghai 200031 China

Within the framework of a multiphase transport model, we study the production and properties of Ω andφ in Au ＋ Au collisions with a new set of parameters for （s（NN））^（1/2）= 200 GeV and with the original set of parameters for （s（NN））^（1/2）= 11.5 GeV. The AMPT model with string melting provides a reasonable description at （s（NN））^（1/2）= 200 GeV,while the default AMPT model describes the data well at （s（NN））^（1/2）= 11.5 GeV. This indicates that the system created at top RhIC energy is dominated by partonic interactions, while hadronic interactions become important at lower beam energy, such as （s（NN））^（1/2）= 11.5 GeV. The comparison of N（Ω^＋＋Ω^-）/[2N（φ）] ratio between data and calculations further supports the argument. Our calculations can generally describe the data of nuclear modification factor as well as elliptic flow.

关键词： multi-strangeness particles AMPT RhIC

A transmission electron microscopy study of microscopic causes for localized-corrosion morphology variations in the AA7055 Al alloy

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journal of Materials Science & Technology 2018年第10期34卷 1719-1729页

作者： X.B. Yang j.h. chen G.h. Zhang L.P. huang T.W. Fan Y. Ding X.W. Yu Center for high-Resolution Electron Microscopy College of Materials Sdence and Engineering Hunan University Changsha Hunan 410082 China Department of Applied Physics School of Physics and Electronics Hunan University Changsha Hunan 410082 China

By Using （scanning） transmission electron microscopy, localized-corrosion morphology variations of the AA7055 AIZn（Cu）Mg alloy with different thermal processes and their underlying microscopic causes were investigated systematically. Our study shows that the corrosion resistance of the nanoscale precipitates varies with their structure type and Cu-content. just like the Al-matrix, the early-stage precipitates are corrosion resistant, as compared with the ηp/η-precipitates without high Cu-content. With a high Cu-content, however, the η-precipitates become most corrosion resistant among all phases involved. hence, tailoring the precipitate microstructure and chemistry though thermal processes may change the overall corrosion morphology and improve corrosion resistance property of the alloy.

关键词： Aluminum alloys Precipitates Corrosion Electron microscopy

φ-meson production in heavy-ion collisions at RhIC

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φ-meson production in heavy-ion collisions at RHIC

COMPUTER SIMULATION OF NEURAL NETWORK CONTROL SYSTEM FOR CO_2 WELDING PROCESS

The 6th China-Nuclear Physics Symposium

作者： j.h. chen for the STAR collaboration Shanghai Institute of Applied Physics, CAS

Studying properties of phi-mesons produced in heavy-ion collisions can provide information about the hot and dense medium created in the collisions. Since the interaction cross-section for phi with other copiously produced hadrons is presumed to be small, and its lifetime relatively long (41 fm/c), the phi-meson should be a clean probe of the medium from the early stage of the system’s evolution. Additionally, since

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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 187-193页

作者： D. Fan B. Li Y.Z. Ma and j.h. chen (Welding Institute, Gansu University of Technology,Lanzhou 730050, China)

In this paper, neural network control systems for decreasing the spatter of CO2 welding have been created. The Generalized inverse Learning Architecture(GILA), the SPecialized inverse Learning Architecture(SILA)-I & h and the Error Back Propagating Model(EBPM) are adopted respectively to simulate the static and dynamic welding control processes. The results of simulation and experiment show that the SILA-I and EBPM have betted properties. The factors affecting the simulating results and the dynamic response quality have also been analyzed.

关键词： welding spatter neural network control simulation

Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua Zhang Lingjing chen huatian Shi Yue Wei Gui chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （hCOO-）.Turnover number （TON） for hCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1h-benzo[d]imidazole （BIh） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NhBF4also produced hCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-h]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo ChIARADIA Chao WU huayong chen Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（hich are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 120-129页

作者： YANG Mei ZhANG Mingzhe chen hao School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-h gel with Mg^(2+)and Oh-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

Late Paleozoic–Early Mesozoic tectonic evolution of the Zongwulong Shan-Qinghai Nanshan tectonic belt in the northern Qaidam continent， northern Tibet

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journal of Earth Science 2025年

作者： Yonghui Zhao chen Wu jie Li Peter j.h.proff Lin Ding State Key Laboratory of Tibetan Plateau Earth System and Resources Environment (TPESRE)， Institute of Tibetan Plateau Research， Chinese Academy of Sciences University of Chinese Academy of Sciences Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development， Chongqing University of Science and Technology Department of Earth and Ocean Sciences， University of North Carolina Wilmington

The Zongwulong Shan-Qinghai Nanshan tectonic belt of the northern Tibet Plateau experienced a protracted tectonic history， including the openings and closures of the Proto- and Paleo-Tethyan Oceans. Although the tectonic belt has been extensively studied， details regarding the tectonic processes involved in its development remain controversial. To better constrain the tectonic processes of this tectonic belt， we conducted detailed field geological mapping， zircon U-Pb geochronology， and whole-rock geochemical and Sr-Nd isotopic analyses. Our results show that intrusive rocks in the tectonic belt crystallized in ca. 292–233 Ma， perhaps in an arc/subduction setting. Geochemical and Sr-Nd isotopic data suggest that early Permian–late Triassic ultramafic-intermediate intrusions were sourced from the enriched mantle， whereas intermediate-acidic rocks were sourced from mixed crust-mantle. We present the tectonic model that involves: (1) Early Devonian–early Permian intracontinental extension occurred in the northern margin of the Qaidam continent (ca. 416 Ma–292 Ma); (2) Early Permian–late Triassic northward subduction of the Paleo-Tethyan Ocean resulted in arc magmatism (ca. 292 Ma–233 Ma); and (3) subsequent late Triassic intracontinental extension (ca. 233 Ma–215 Ma). Our results suggest that the late Paleozoic–early Mesozoic development of the Zongwulong Shan-Qinghai Nanshan was related to the opening， subduction， and slab retreat of the Paleo-Tethyan Ocean， which has key implications for the tectonic evolution of the northern Tibetan Plateau.

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Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic h2O2 synthesis coupled with biomass valorization

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journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： jiaye Li Shuang Pan Yihuang chen Qiong Liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （h2O2） synthesis presents a green and costeffective production ***,achieving highly selective h2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to h2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for h2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of h2O2coupled with biomass valorization.

关键词： Free radical reactions